Technical Field
The present disclosure relates to a syringe.
Background Art
A prefilled syringe in which a sterilized syringe outer tube is filled with a liquid product in an aseptic manner is known (see, for example, WO 2011/108574 A). The prefilled syringe disclosed in WO 2011/108574 A includes: the syringe outer tube having a spout through which the liquid product is ejected, and a lock adapter rotatably supported at the spout; and a cap mounted on the spout of the syringe outer tube. Also, the cap includes a cap main body that seals the spout in a liquid-tight manner, a mounting section disposed on a proximal end side of the cap main body and mounted on an outer circumferential portion of the spout, and a breaking section that links the cap main body with the mounting section and can release the link by breaking.
In this cap, the cap main body is rotated around an axis of the syringe outer tube with respect to the mounting section, thereby breaking the breaking section to separate the cap main body from the mounting section. Further, the cap main body that has been once separated from the mounting section cannot be mounted again on the spout, in other words, the cap main body is configured incapable of recapping the spout. This makes it possible to avoid using the prefilled syringe once opened erroneously, deeming the prefilled syringe as in the unused state.
However, there is a case in the prefilled syringe disclosed in WO 2011/108574 A, where stress that may exceed a breaking limit of the break section breakage is generated at the breaking section when external force is applied to the cap main body at the time of transport, for example. In this case, there is a problem in that the breaking section is undesirably broken.